Fix styling

[markijbema]

I tried to make it such that we pass the rubocop tests, to make it easy to have consistent formatting. For now we have two exceptions:

• Class/module level documentation We don't have this yet, and to write this just for rubocop conformance felt like yak shaving ;)
• Define methods with parentheses We currently follow seatttle.rb formatting, which imho is just as good, so saw no need to fix this.

[tomdev]

Nice, lot cleaner.